possible effect of green tea [catechin] on perinephric fat adipocytes of adult male albino rat after induction of obesity: a histological study

ABSTRACT

Green tea is one of the most widely consumed beverages in the world, and its antioxidant properties have been widely explored. Its active ingredients [polyphenols are believed to be responsible for most of green tea's roles in promoting good health Obesity and its associated metabolic disorders are an increasingly prevalent conditior in different societies. The aim of this research is to study the effect of diet-induced obesity on the histological structure of adipocytes and to evaluate the possible protective role of green tea. Forty adult male rats were divided into three groups. Group I rats [control group, n = 10] were given a balanced diet for 6 weeks. Group II rats [n = 10] were given a high-energy fatty diet for 6 weeks and served as the affected group. Group III rats [green tea group, n = 20] were divided into two subgroups. Subgroup IIIa rats [lowúdose group, n = 10] were given a high-energy fatty diet for 6 weeks and a low dose of green tea extract [325 mg/kg/day] by an oral tube for the last 4 weeks. Subgroup IIIb rats [high-dose group, n = 10] were given a high-energy fatty diet for 6 weeks and a high dose of green tea extract [500 mg/kg/day] by an oral tube for the last 4 weeks. After 6 weeks, the animals were weighed, killed, and specimens from perinephric fat were prepared for light microscopic [sudan III and osmic acid stains] and electron microscopic [transmission and scanning electron microscopic] studies. The mean area of unilocular fat cells [micrometer square] was measured and statistically studied. There was a significant increase in body weight and in marked adipocyte morphological and cytological changes [size of adipocytes, saturated fatty acids within fat cells, and increased mitochondrial content] in groups II and IIIa compared with the control group. Such effects were ameliorated by concomitant administration of high-dose green tea extract in group IIIb. It could be concluded that high-dose green tea extract is effective in lowering the increased body weight due to a high-energy fatty diet. Hence, it is advised to consider a high dose of green tea extract effective against diet-induced obesity through its effect on size and structure of adipocyte